crear miniaturas php+gd

[toplucho]

Ya pude que funcionara parcialmente.

Código PHP:

 <a href="fotos/<? echo($row[foto]); ?>" class="link_gris1" rel="lightbox" title="<? echo($row[descripcion]); ?>"><img src="fotos/mini.php?image=<? echo($row[foto]); ?>&tamano=200" /></a>  

pero no se porque sale los recuadros en pequeño pero no las imagenes, y ademas se ha generado un archivo log (error_log)con mensajes de errores:

[27-Jun-2008 16:41:12] PHP Warning: imagesx(): supplied argument is not a valid Image resource in /home/maquinas/public_html/fotos/mini.php on line 9
[27-Jun-2008 16:41:12] PHP Warning: imagesy(): supplied argument is not a valid Image resource in /home/maquinas/public_html/fotos/mini.php on line 10
[27-Jun-2008 16:41:12] PHP Warning: Division by zero in /home/maquinas/public_html/fotos/mini.php on line 14
[27-Jun-2008 16:41:12] PHP Warning: imagecreatetruecolor() [<a href='function.imagecreatetruecolor'>function.imag ecreatetruecolor</a>]: Invalid image dimensions in /home/maquinas/public_html/fotos/mini.php on line 19
[27-Jun-2008 16:41:12] PHP Warning: imagecopyresampled(): supplied argument is not a valid Image resource in /home/maquinas/public_html/fotos/mini.php on line 22
[27-Jun-2008 16:41:12] PHP Warning: imagejpeg(): supplied argument is not a valid Image resource in /home/maquinas/public_html/fotos/mini.php on line 25
[27-Jun-2008 16:41:12] PHP Warning: imagedestroy(): supplied argument is not a valid Image resource in /home/maquinas/public_html/fotos/mini.php on line 28
[27-Jun-2008 16:42:23] PHP Warning: imagecreatefromjpeg($row[foto]) [<a href='function.imagecreatefromjpeg'>function.image createfromjpeg</a>]: failed to open stream: No such file or directory in /home/maquinas/public_html/fotos/mini.php on line 6
[27-Jun-2008 16:42:23] PHP Warning: imagesx(): supplied argument is not a valid Image resource in /home/maquinas/public_html/fotos/mini.php on line 9
[27-Jun-2008 16:42:23] PHP Warning: imagesy(): supplied argument is not a valid Image resource in /home/maquinas/public_html/fotos/mini.php on line 10
[27-Jun-2008 16:42:23] PHP Warning: Division by zero in /home/maquinas/public_html/fotos/mini.php on line 14
[27-Jun-2008 16:42:23] PHP Warning: imagecreatetruecolor() [<a href='function.imagecreatetruecolor'>function.imag ecreatetruecolor</a>]: Invalid image dimensions in /home/maquinas/public_html/fotos/mini.php on line 19
[27-Jun-2008 16:42:23] PHP Warning: imagecopyresampled(): supplied argument is not a valid Image resource in /home/maquinas/public_html/fotos/mini.php on line 22
[27-Jun-2008 16:42:23] PHP Warning: imagejpeg(): supplied argument is not a valid Image resource in /home/maquinas/public_html/fotos/mini.php on line 25
[27-Jun-2008 16:42:23] PHP Warning: imagedestroy(): supplied argument is not a valid Image resource in /home/maquinas/public_html/fotos/mini.php on line 28